The last sentence of this article reads: Ultimately, conservatives don't have much to worry about, seeing as U.S. ratification requires a two-thirds majority in the Senate โ a threshold that, even with a Democratic majority, isn't likely to be met. Chalk up another victory for freedom. :)
Still, should we worry? Read the article.
http://theweek.com/article/index/250210/why-gun-owners-fear-the-united-nations